Process for protecting protein fibrous materials



v Patented July 9, 1940 UNITED STATES PROCESS FOR PROTECTING PROTEIN FIBROUS MATERIALS Ruth E. Elmquist,

Washington, D. 0., and Harry Humfeld and James H. Kettering, Arlington,

No Drawing.

Application June 26, 1937,

Serial No. 150,548

4 Claims.

(Granted under the act of' March April 30, 1928; 370 0.

amended This application is made under the act of March 3, 1883, as amended by the act of April 30, 1928, and the invention herein described, it patented, may be manufactured and used by or 5 for the Government of the United States of America for governmental purposes without the payment to us of any royalty thereon.

We hereby dedicate the invention herein described to the free use of the people of the United 10 States of America to take efiect on the granting of a patent to us.

This invention relates to a method for sterilizing and disinfecting textile and other fibrous materials of animal origin.

At the present time, no satisfactory method is available for this purpose. Our invention is a new and valuable process consisting of the use of tetrachlorethylene in conjunction with heat for sterilizing fabrics and other fibrous materials of animal origin. The process is also valuable for sterilizing raw textile materials such as wool, mohair, bristle, horse-hair, silk, shoddy, and other natural and artificial textile materials largely protein in nature and articles which may 25 be manufactured from them.

Since the tetrachlorethylene employed in the dry cleaning industry may be used in our procedure, household and institutional textiles and articles of clothing can be cleaned and sterilized 30 in one operation by our process.

Tetrachlorethylene also is valuable for degreasing purposes, such as removing fats from raw wool during scouring. By our process raw wool can be degreased and sterilized in one operation.

35 This method of scouring may avoid all danger from animal borne infectious diseases.

As specific examples, we may use the following procedures:

We place the material to be sterilized in a vessel containing sufficient tetrachlorethylene, depending upon the quantity of the material, to cover the material and place the vessel in a steam autoclave. We then subject the immersed material to a temperature of 275 F. for 1 hour, or of 45 250 F. for 2 hours, or of 212 F. for 24 hours. We then take the material from the solvent and remove the excess liquid by standard dry cleaning methods, by washing in alcohol and then in water, or by evaporating in a current 50 of warm air.

Wedo not restrict ourselves to the particular temperature and time stated, as any temperature of 212 F. or higher may be employed provided a sufllcient period .cf time is used. The condi- 55 tions producing minimal damage may be selected from the data presented.

As further proof of the value of our invention, we submit the following data:

liquid therefrom.

Breaking strength, thread count, and index: of

two fabrics sterilized by means of terachlorethylene Materiel Treatment g fg fgg g Index Pounds Pounds Number per yam Control 52. 76. 3 0. 69 'letrachlorethylone for 52.1 79. 7 65 24 hrs. at F. wool Tetrachlorethylene iorl 51.5 77. 0 67 hnat 275 F.

Water ior 24 hrs. at 35. 3 81. 4 43 212' F. Water for 1 hr. at 275 F. 0 95. 4 00 Control 69. 2 56. 5 1. 22 Tetrachlcrethylene for 61. 7 58. 4 l. 06

24 hrs. at Tetrachorethylene for 2 66. 4 58.0 1.14

hrs. 250 1?. Silk. Tetrachlorethylene for 1 54. 5 59. 9 91 hr. at 275 Water for 12 hrs. at 57. 7 59.0 .98

212 F. Water ior2hrs.at250 F 64.3 59.0 i. 0 Water for 1 hr. at 275 F. 57.0 59. 8 95 Samples of these fabrics were inoculated with a heavy spore suspension of Bacillus mesentericus, one of the most resistant spore formers known. They were then sterilized by the treatments described above. When the fabric samples were placed on nutrient agar and incubated, they were found to be sterile.

Having thus described our invention. what we claim for Letters Patent is:

1. A process for protecting protein fibrous materials, which comprises subjecting said materials to the action of heat ranging from 212 F. to 275 F. for periods from 24 to 1 hour, the while immersed in tetrachlorethylene, and thence removing the excess liquid therefrom.

2. A process for protecting wool, which comprises subjecting said material to the action of heat ranging from 212 F. to 275 F. for periods from 24 to 1 hour, the while immersed in tetrachlorethylene, and thence removing the excess liquid therefrom.

3. A process for protecting silk, which comprises subjecting said material to the action of heat ranging from 212 F. to 275 F. for periods from 24 to 1 hour, the while immersed in tetrachlorethylene, and thence removing the excess liquid therefrom.

4. A process for protecting mohair, which comprises subjecting said material to the action of heat ranging from 212 F. to 275 F. for periods from 24 to 1 hour, the while immersed in tetrachlorethylene, and thence removing the excess RUTH E. ELMQUIST. HARRY HUNIFELD. JAMES H. KETTERING. 

